1

Management

of Patients With

SupraventricularArrhythmias

ACC/AHA Pocket Guideline

Based on the ACC/AHA/ESC Guidelines on the Management of Patients With Supraventricular Arrhythmias

March 2004

Management of Patients With

SupraventricularArrhythmiasMarch 2004

ACC/AHA/ESC Writing Committee

Carina Blomström-Lundqvist,

MD, PhD, FACC, FESC, Co-chair

Melvin M. Scheinman, MD, FACC, Co-chair

Etienne M. Aliot, MD, FACC, FESC

Joseph S. Alpert, MD, FACC, FAHA, FESC

Hugh Calkins, MD, FACC, FAHA

A. John Camm, MD, FACC, FAHA, FESC

W. Barton Campbell, MD, FACC, FAHA

David E. Haines, MD, FACC

Karl H. Kuck, MD, FACC, FESC

Bruce B. Lerman, MD, FACC

D. Douglas Miller, MD, CM, FACC

Charlie W. Shaeffer, Jr., MD, FACC, FAHA

William G. Stevenson, MD, FACC

Gordon F. Tomaselli, MD, FACC, FAHA

Evaluation/Managem

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rrhythmias

© 2004 American College

of Cardiology Foundation and

American Heart Association, Inc.

The following article was adapted from the

ACC/AHA/ESC Guidelines for the Management

of Patients With Supraventricular Arrhythmias (J

Am Coll Cardiol 2003;42:1493-531; Circulation

2003;108:1871-909; European Heart Journal

2003;24:1857-97). For a copy of the full report

or Executive Summary as published in the Journal

of the American College of Cardiology, Circulation,

and the European Heart Journal, visit our Web

sites at www.acc.org, www.americanheart.org, or

www.escardio.org or call the ACC Resource

Center at 1-800-253-4636, ext. 694.

Contents

I. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

II. General Evaluation and Management . . . . . . . . . . . . . . . . . . . . . . 6

A. Patients Without Documented Arrhythmia . . . . . . . . . . . . . . . . . . . . . . . . 6

B. Patients With Documented Arrhythmia . . . . . . . . . . . . . . . . . . . . . . . . . . 6

III. Specific Arrhythmias . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

A. Inappropriate Sinus Tachycardia . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

B. Atrioventricular Nodal Reciprocating Tachycardia (AVNRT) . . . . . . . . . . . 17

C. Focal and Nonparoxysmal Junctional Tachycardia. . . . . . . . . . . . . . . . . . 20

D. Atrioventricular Reciprocating Re-entry Tachycardia

(Extranodal Accessory Pathways) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

E. Focal Atrial Tachycardia . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

F. Macro–Re-entrant Atrial Tachycardia . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

G. Special Circumstances . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

I. Introduction

Supraventricular arrhythmias (SVAs) include

rhythms emanating from the sinus node, atrial

tissue [atrial tachycardias (ATs), atrial flutter], and

junctional tissue [atrioventricular nodal reciprocat-

ing tachycardia (AVNRT)]. Accessory pathway-

mediated and atrioventricular reciprocating tachy-

cardia (AVRT) are also included. SVA occurs in all

age groups and may be associated with minimal

symptoms, such as palpitations, or may present

with syncope. In some conditions (i.e., those

associated with bypass tracts), arrhythmias may be

life-threatening. The prevalence of paroxysmal

supraventricular tachycardia (PSVT) is 2 to 3 per

1,000. Over the past decade, impressive advances

in curative treatment modes (catheter ablation)

have become available. The purpose of this booklet

is to summarize guidelines for use of drug and abla-

tive procedures for patients with supraventricular

tachycardia (SVT). Guidelines for treatment of atrial

fibrillation were recently published; hence, this sub-

ject is excluded in the present booklet. In addition,

SVT in the pediatric population is excluded. The

ACC/AHA/ESC Pocket Guidelines for the Management

of Patients With Atrial Fibrillation discusses antiar-

rhythmic drug doses and adverse effects, and

therefore, this will not be repeated.

4 5

The guidelines outlined come from an expert committee select-

ed by the European Society of Cardiology, American College of

Cardiology, and American Heart Association. The ultimate judg-

ment regarding care of a particular patient must be made by

the physician and patient in light of all of the circumstances

presented by that patient. In some circumstances, deviations

from these guidelines may be appropriate. Recommendations

are provided in tables and use the following classification out-

line, summarizing both the evidence and expert opinion:

Class I Conditions for which there is evidence and/or

general agreement that the procedure or treatment

is useful and effective.

Class II Conditions for which there is conflicting evidence

and/or a divergence of opinion about the useful-

ness/efficacy of a procedure or treatment.

Class IIa The weight of evidence or opinion is in

favor of the procedure or treatment.

Class IIb Usefulness/efficacy is less well estab-

lished by evidence or opinion.

Class III Conditions for which there is evidence and/or

general agreement that the procedure or treatment

is not useful/effective and in some cases may be

harmful.

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6 7

Figure 1

II. General Evaluation and Management

A. Patients Without Documented Arrhythmia (Figure 1)

Clinical History

Distinguish whether palpitations are regular or

irregular.

■ Pauses or dropped beats followed by a sensation

of a strong heartbeat support presence of premature

beats.

■ Irregular palpitations may be due to premature

extra beats, atrial fibrillation, or multifocal AT.

■ Regular and recurrent palpitations with abrupt

onset and termination are designated as parox-

ysmal (also referred to as PSVT). Termination by

vagal maneuvers suggests a re-entrant tachycardia

involving atrioventricular nodal tissue (e.g.,

AVNRT, AVRT).

■ Sinus tachycardia is nonparoxysmal and

accelerates and terminates gradually.

B. Patients With Documented Arrhythmia

1. Narrow QRS-Complex Tachycardia

If the ventricular action on ECG (QRS) is narrow [less

than 120 milliseconds (ms)], then the tachycardia is

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Initial evaluation of patients with suspected tachycardia.

AF indicates atrial fibrillation; AV, atrioventricular; AVRT, atrioventricular reciprocating tachycardia;ECG, electrocardiogram; MAT, multifocal atrial tachycardia.

Clinical history of palpitations12-Lead ECG (sinus rhythm)

Assess arrhythmia pattern by clinical history

Suspect AF, MAT,or atrial flutter

with variable AV conduction

Pre-excitation

Suspect AVRT

History of syncope?

Event monitor and follow-up

Sustained regular palpitations

Refer to arrhythmia specialist

Irregular palpitations

▼

Yes No

(exclude heart disease)

Yes

No

▼▼

▼▼

▼

▼ ▼

▼

No▼

Yes

▼

No

No▼

Yes

▼

Yes

Figure 2

▼

9

almost always supraventricular, and the differential diagnosis

relates to its mechanism (Figure 2). The clinician must deter-

mine the relationship of the P waves to the ventricular complex

(Figure 3). Responses of narrow QRS-complex tachycardias

to adenosine (Figure 4) or carotid massage may aid in the

differential diagnosis.

2. Wide QRS-Complex Tachycardia

At times, the patient will present with rapid wide-complex

(greater than 120 ms) tachycardia, and the clinician must

decide whether the patient has

a) SVT with bundle-branch block (BBB) (or aberration),

b) SVT with atrioventricular (AV) conduction over an

accessory pathway, or

c) ventricular tachycardia (VT).

This categorization depends not only on the relation of the

P wave to the QRS but also on specific morphologic findings,

especially in the precordial leads (Figure 5).

3. Management

If the diagnosis of SVT cannot be proven, the patient should be

treated as if VT were present. Medications for SVT (verapamil or

diltiazem) may precipitate hemodynamic collapse in a patient

with VT. Special circumstances (i.e., pre-excited tachycardias

and VT due to digitalis toxicity) may require alternative therapy.

Immediate direct-current (DC) cardioversion is the treatment of

choice for any hemodynamically unstable tachycardia.

8

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Differential diagnosis for narrow QRS-complex tachycardia.

Patients with focal junctional tachycardia may mimic the pattern of slow-fast AVNRTand may show AV dissociation and/or marked irregularity in the junctional rate.AV indicates atrioventricular; AVNRT, atrioventricular nodal reciprocating tachycardia; AVRT, atrioventricular reciprocating tachycardia; MAT, multifocal atrial tachycardia; ms, milliseconds; PJRT, permanent form of junctionalreciprocating tachycardia; QRS, ventricular activation on electrocardiogram.

Narrow QRS tachycardia(QRS duration less than 120 ms)

Regular tachycardia?

Visible P waves?

Atrial flutter or Atrial tachycardia Analyze RP interval

Short (RP shorter than PR)

RP shorter than 70 ms

AVNRT

RP longer than 70 ms

■ AVRT■ AVNRT■ Atrial tachycardia

▼

■ Atrial tachycardia■ PJRT■ Atypical AVNRT

Long (RP longer than PR)

Atrial rate greater than ventricular rate?

■ Atrial fibrillation

■ Atrial tachycardia/ flutter with variable AV conduction

■ MAT

▼

▼

▼

▼

■ Inadequate dose/delivery

■ Consider VT (fascicular or high septal origin)

■ Sinus tachycardia

■ Focal AT

■ Non paroxysmaljunctional tachycardia

■ AVNRT

■ AVRT

■ Sinus node re-entry

■ Focal AT

■ Atrial flutter

■ AT

10 11

Figure 4

Figure 3

Indications for referral to a cardiac

arrhythmia specialist:

■ All patients with Wolff-Parkinson-White (WPW)

syndrome (pre-excitation plus arrhythmias).

■ All patients with severe symptoms during

palpitations, such as syncope or dyspnea.

■ Wide QRS-complex tachycardia of

unknown origin.

■ Narrow QRS-complex tachycardias with drug

resistance, drug intolerance, or desire to be free

of drug therapy.

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Electrocardiograph tracing with limb leads I, II, and III, showingan RP (initial R to initial P) interval longer than the PR interval.

The P wave differs from the sinus P wave.

Responses of narrow-complex tachycardias to adenosine.

AT indicates atrial tachycardia; AV, atrioventricular; AVNRT, atrioventricular nodal reciprocating tachycardia;AVRT, atrioventricular reciprocating tachycardia; IV, intravenous; QRS, ventricular activation on electrocardiogram;VT, ventricular tachycardia.

▼ ▼ ▼ ▼

▼

Regular narrow QRS-complex tachycardia

IV adenosine

No change in rateGradual slowing

then reaccelerationof rate

Suddentermination

Persisting atrialtachycardia

with transient high-grade AV block

▼▼

▼

Typical RBBBor LBBB

▼ ▼ ▼ ▼

12 13

Figure 5

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*Concordant indicates that all precordial leads show either positive or negative deflections. Fusion complexes are diagnostic of VT.

† In pre-excited tachycardias, the QRS is generally wider (i.e., more pre-excited) than in sinus rhythm.

A indicates atrial; AF, atrial fibrillation; AP, accessory pathway; AT, atrial tachycardia; AV, atrioventricular;AVRT, atrioventricular reciprocating tachycardia; BBB, bundle-branch block; LBBB, left bundle-branch block;ms, milliseconds; QRS, ventricular activation on ECG; RBBB, right bundle-branch block; SR, sinus rhythm;SVT, supraventricular tachycardias; V, ventricular; VF, ventricular fibrillation; VT, ventricular tachycardia.

Differential diagnosis for wide QRS-complex tachycardia (greater than 120 ms).

A QRS conduction delay during sinus rhythm, when available for comparison,reduces the value of QRS morphology analysis. Adenosine should be used with caution when the diagnosis is unclear because it may produce VF in patients with coronary artery disease and AF with a rapid ventricular rate in pre-excitedtachycardias. Various adenosine responses are shown in Figure 6.

▼

▼

▼

Wide QRS-complex tachycardia(QRS duration greater than 120 ms)

Regular or irregular?

Regular

1 to 1 AV relationship?

QRS morphology in precordial leads

▼

■ Atrial fibrillation■ Atrial flutter /AT with variable conduction anda. BBB orb. antegrade conduction via AP

▼▼

Irregular

Yes or unknown▼▼

No

V rate faster than A rate

VT

A rate faster than V rate

■ Atrial tachycardia■ Atrial flutter

▼ ▼

Vagal maneuvers or adenosine

Is QRS identical to that during SR? If yes consider:■ SVT and BBB■ Antidromic AVRT†

Previous myocardial infarction or structural heart disease? If yes, VT is likely.

}SVT

Precordial leads■ Concordant*

■ No R/S pattern■ Onset of R to nadirlonger than 100ms

}VT

RBBB pattern■ qR, Rs, or Rr1 in V1

■ Frontal plane axis range from +90 degrees to -90 degrees

}VT

LBBB pattern■ R in V1 longer than 30 ms■ R to nadir of S in V1

greater than 60ms■ qR or qS in V6

}VT

▼ ▼

▼

▼

Termination

▼

Yes No, persistenttachycardia with

AV Block

■ Vagal maneuvers■ IV adenosine†

■ IV verapamil/diltiazem■ IV beta blocker

▼ ▼

▼ ▼

▼

▼

Termination

DC cardioversion

▼▼

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Figure 6

14

Recommendations for Acute Management ofHemodynamically Stable and Regular Tachycardia

ECG Recommendation* Class Evidence

Narrow QRS-complextachycardia (SVT)

Wide QRS-complex tachycardia

■ SVT and BBB

■ Pre-excited SVT/AF†

■ Wide QRS-complextachycardia of unknownorigin

Wide QRS-complex tachycardia of unknownorigin in patients withpoor LV function

Vagal maneuvers I BAdenosine I AVerapamil, diltiazem I ABeta blockers IIb CAmiodarone IIb CDigoxin IIb C

See above

Flecainide‡ I BIbutilide‡ I BProcainamide,‡ I BDC cardioversion I C

Procainamide‡ I BSotalol‡ I BAmiodarone I BDC cardioversion I BLidocaine IIb BAdenosine§ IIb CBeta blockers†† III CVerapamil** III B

Amiodarone I BDC cardioversion, lidocaine I B

The order in which treatment recommendations appearin this table within each class of recommendation doesnot necessarily reflect a preferred sequence of adminis-tration. Please refer to text for details. For pertinent drug dosing information, please refer to the ACC/AHA/ESC Guidelines for the Management of Patients With Atrial Fibrillation.

*All listed drugs are administered intravenously.

† See Section III-D.

‡ Should not be taken by patients with reduced LV function.

§ Adenosine should be used with caution in patients withsevere coronary artery disease because vasodilation of

normal coronary vessels may produce ischemia in vulner-able territory. It should be used only with full resuscita-tive equipment available.

†† Beta blockers may be used as first-line therapy for thosewith catecholamine-sensitive tachycardias, such as rightventricular outflow tachycardia.

** Verapamil may be used as first-line therapy for thosewith LV fascicular VT.

AF indicates atrial fibrillation; BBB, bundle-branch block;DC, direct current; ECG, electrocardiogram;LV, left ventricular; QRS, ventricular activation on ECG;SVT, supraventricular tachycardia.

15

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Acute management of patients with hemodynamically stable and regular tachycardia.

* A 12-lead ECG during sinus rhythm must be available for diagnosis.

† Adenosine should be used with caution in patients with severe coronary artery disease and may produce AF,which may result in rapid ventricular rates for patients with pre-excitation.

** Ibutilide is especially effective for patients with atrial flutter but should not be used in patients with an ejection fraction less than 30% because of increased risk of polymorphic VT.

AF indicates atrial fibrillation; AV, atrioventricular; BBB, bundle-branch block; DC, direct current; ECG, electrocar-diogram; IV, intravenous; LV, left ventricular; QRS, ventricular activation on ECG; SVT, supraventricular tachycardia;VT, ventricular tachycardia.

Hemodynamically stable regular tachycardia

Narrow QRS

SVT

Yes No

Wide QRS

Definite SVT(see narrow QRS)

VT or unknown mechanism

■ IV procainamide■ IV sotalol■ IV lidocaine(IV amiodarone inpatients with poor LV function)

▼ ▼

SVT+BBB*

Pre-excited SVT*

■ IV ibutilide**

■ IV procainamide■ IV flecainide

■ or overdrive pacing /DC cardioversion

}plus AV-nodal-blocking agents

16 17

III. Specific Arrhythmias

A. Inappropriate Sinus Tachycardia

Inappropriate sinus tachycardia refers to a persis-

tent increase in resting heart rate unrelated to the

level of physical, emotional, pathological, or phar-

macological stress. Approximately 90% of patients

are female. The degree of disability can vary from

asymptomatic to individuals who are totally inca-

pacitated.

The diagnosis is based on the following criteria:

■ Persistent sinus tachycardia (heart rate greater

than 100 bpm) during the day with excessive rate

increase in response to activity and nocturnal

normalization of rate as confirmed by a 24-hour

Holter recording.

■ The tachycardia and its symptoms are

not paroxysmal.

■ P-wave morphology is identical to sinus rhythm.

■ Exclusion of a secondary systemic cause

(hyperthyroidism, pheochromocytoma, physical

deconditioning).

Treatment

The treatment is predominantly symptom driven. The long-

term success rate of sinus node modification by catheter abla-

tion has been reported to be approximately 66%. The diagnosis

of postural orthostatic tachycardia syndrome must be excluded

before ablation is considered.

Recommendations for Treatment of Inappropriate Sinus Tachycardia

Treatment Recommendation Class Evidence

Medical Beta blockers I C

Verapamil, diltiazem IIa C

Interventional Catheter ablation-sinus node IIb Cmodification/elimination*

The order in which treatment recommendations appear in this table within each class of recommendation does notnecessarily reflect a preferred sequence of administration. Please refer to text for details. For pertinent drug dosinginformation, please refer to the ACC/AHA/ESC Guidelines for the Management of Patients With Atrial Fibrillation.

* Used as a last resort.

B. Atrioventricular Nodal Reciprocating Tachycardia (AVNRT)

AVNRT is a re-entry tachycardia that involves the AV node and

perinodal atrial tissue. One pathway (fast) is located near the

superior portion of the AV node and the other (slow) along the

septal margin of the tricuspid annulus. During typical AVNRT

(85-90%), antegrade conduction occurs over the slow pathway,

with a turnaround point in the AV junction, and retrograde con-

duction occurs over the fast pathway. The converse is found

during atypical AVNRT, resulting in a long R-P tachycardia with

negative P waves in III and AVF inscribed before the QRS.

Specific Arrhythm

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Arr

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18 19

Treatment

Standard treatment is use of drugs that primarily

block AV nodal conduction (beta blockers, calcium

channel blockers, adenosine). Another treatment

option that has been shown to be effective and

safe involves catheter ablation to destroy the slow

pathway. Indications for ablation depend on clinical

judgment and are often predicated on patient

preference. Factors that contribute to the decision

include tachycardia frequency, tolerance of symp-

toms, and patient inclination relative to chronic

drug therapy vs. ablation. The patient must accept

the risk, albeit small (less than 1%), of AV block

and pacemaker insertion.

Recommendations for Long-Term Treatment of Patients With Recurrent AVNRT

Clinical Presentation Intervention Class Evidence

Poorly tolerated AVNRT with hemodynamic intolerance

Recurrent symptomatic AVNRT

Recurrent AVNRT unre-sponsive to beta blockadeor calcium channel blockerand patient not desiringRF ablation

AVNRT with infrequent orsingle episode in patientswho desire complete control of arrhythmia

Documented PSVT withonly dual AV-nodal pathways or single echobeats demonstrated dur-ing electrophysiologicalstudy and no other identified cause of arrhythmia

Infrequent,well-tolerated AVNRT

Catheter ablation I BVerapamil, diltiazem,beta blockers, sotalol,amiodarone IIa CFlecainide,* propafenone* IIa C

Catheter ablation I BVerapamil I BDiltiazem, beta blockers I CDigoxin† IIb C

Flecainide,* propafenone,* sotalol IIa BAmiodarone IIb C

Catheter ablation I B

Verapamil, diltiazem, beta blockers,flecainide,* propafenone* I CCatheter ablation‡ I B

No therapy I CVagal maneuvers I B

“Pill-in-the-pocket” I BVerapamil, diltiazem,beta blockers I BCatheter ablation I B

The order in which treatment recommendations appear in this table within each class of recommendation does not necessarily reflect a preferred sequence of administration. Please refer to text for details. For pertinent drug dosing information, please refer to the ACC/AHA/ESCGuidelines for the Management of Patients With Atrial Fibrillation.

* Relatively contraindicated for patients with coronary artery disease, left ventricular dysfunction,or other significant heart disease.

† Often ineffective because pharmacological effects can be overridden by enhanced sympathetic tone.

‡ Decision depends on symptoms.

AV indicates atrioventricular; AVNRT, atrioventricular nodal reciprocating tachycardia;LV, left ventricular; PSVT, paroxysmal supraventricular tachycardia; RF, radiofrequency.

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20 21

C. Focal and Nonparoxysmal Junctional Tachycardia

1. Focal Junctional Tachycardia

The unifying feature of focal junctional tachycardias,

also known as automatic or junctional ectopic

tachycardia, is their origin from the AV node or His

bundle. The ECG features of focal junctional tachy-

cardia include heart rates of 110 to 250 bpm and a

narrow complex or typical BBB conduction pattern

with AV dissociation. Occasionally the junctional

rhythm is quite erratic, suggesting AF. This is a rare

arrhythmia seen in young adults, and if persistent, it

may produce congestive heart failure. Drug therapy

has been associated with only variable success, and

catheter ablative procedures are associated with a

5% to 10% risk of AV block.

2. Nonparoxysmal Junctional Tachycardia

Nonparoxysmal junctional tachycardia is a benign

arrhythmia that is characterized by a narrow-

complex tachycardia with rates of 70 to 120 bpm.

The arrhythmia is thought to be due to abnormal

automaticity or triggered rhythms and serves as a

marker for underlying problems including digitalis

toxicity, postcardiac surgery, hypokalemia, and

myocardial ischemia. Treatment is most often

directed at the underlying condition.

Recommendations for Treatment of Focal and Nonparoxysmal Junctional Tachycardia Syndromes

Clinical Presentation Recommendation Class Evidence

Focal junctional tachycardia

Nonparoxysmal junctional tachycardia

The order in which treatment recommendations appear in this table within each class of recommendation does not necessarily reflect a preferred sequence of administration. Please refer to text for details. For pertinent drug dosing information, please refer to the ACC/AHA/ESC Guidelines for the Management of Patients With Atrial Fibrillation.

* Data available for pediatric patients only.

Beta blockers IIa CFlecainide IIa CPropafenone* IIa CSotalol* IIa CAmiodarone* IIa CCatheter ablation IIa C

Reverse digitalis toxicity I CCorrect hypokalemia I CTreat myocardial ischemia I CBeta blockers, calcium-channel blockers IIa C Specific A

rrhythmiasSp

ecif

ic A

rrhy

thm

ias

■ Pre-excited tachycardias in patients with AT or

atrial flutter with a bystander (not a critical part of

the tachycardia circuit) accessory pathway.

■ Pre-excited atrial fibrillation, the most feared

arrhythmia, occurs in 30% of patients with the

WPW syndrome.

■ PJRT (permanent form of junctional reciprocating

tachycardia): a rare clinical syndrome with a slowly

conducting concealed posteroseptal accessory

pathway characterized by an incessant, long RP

tachycardia with negative P waves in leads II, III,

and aVF.

Sudden Death in WPW Syndrome and Risk Stratification

Markers that identify patients at increased risk

include: 1) a shortest pre-excited R-R interval less

than 250 ms during AF, 2) a history of symptomatic

tachycardia, 3) multiple accessory pathways, and

4) Ebstein’s anomaly. The risk for sudden cardiac

death is estimated at between 0.15% and 0.39% of

patients with WPW syndrome over 3- to 10-year

follow-up.

D. Atrioventricular Reciprocating Re-entry Tachycardia (Extranodal Accessory Pathways)

Typical accessory pathways are extranodal path-

ways that connect the myocardium of the atrium

and the ventricle across the AV groove. Accessory

pathways that are capable of only retrograde con-

duction are referred to as “concealed,” whereas

those capable of anterograde conduction are

“manifest,” demonstrating pre-excitation on a

standard ECG. The term WPW syndrome is re-

served for patients who have both pre-excitation

and tachyarrhythmias.

Several forms of tachycardias may occur:

■ Orthodromic AVRT (most common, 95%) involves

anterograde conduction over the AV node and retro-

grade conduction over the accessory pathway.

■ Antidromic AVRT anterograde conduction over the

accessory pathway and retrograde conduction over

the AV node (or rarely, over a second accessory

pathway) resulting in pre-excited QRS complexes

during tachycardia.

22 23

Specific Arrhythm

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Some patients with infrequent episodes of tachy-

cardia may be managed with the single-dose “pill-

in-the-pocket” approach: taking an antiarrhythmic

drug only at the onset of a tachycardia episode.

This approach to treatment is reserved for patients

without pre-excitation and with uncommon and

hemodynamically tolerated tachycardia.

Catheter ablative techniques are successful in

approximately 95% of cases and have sufficient

efficacy and low risk to be used for symptomatic

patients, either as initial therapy or for patients

experiencing side effects or arrhythmia recurrence

during drug therapy. The type of possible complica-

tions varies depending on the site of the pathway.

The incidence of inadvertent complete AV block

ranges from 0.17% to 1.0% and relates to septal

and posteroseptal accessory pathways. Significant

adverse effects range from 1.8% to 4%, including

a 0.08% to 0.13% risk of death.

24 25

Asymptomatic Patients With Accessory Pathways

The positive predictive value of invasive electro-

physiological testing is too low to justify routine use

in asymptomatic patients. The decision to ablate

pathways in individuals with high-risk occupations,

such as school bus drivers, pilots, and athletes, is

made on individual clinical considerations.

Treatment

Acute Treatment of Patients

With Pre-excited Tachycardias

AV nodal-blocking agents are not effective, and

adenosine may produce AF with a rapid ventricular

rate. Antiarrhythmic drugs that prevent rapid

conduction through the pathway (flecainide,

procainamide, or ibutilide), are preferable, even

if they may not convert the atrial arrhythmia.

Long-Term Therapy

Antiarrhythmic drugs represent one therapeutic

option for management of patients with accessory

pathway–mediated arrhythmias, but they have been

increasingly replaced by catheter ablation. A regi-

men designed for use of drug(s) at the onset of

an episode should only be used for patients with

infrequent, well-tolerated episodes.

Specific Arrhythm

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E. Focal Atrial Tachycardia

Focal ATs are characterized by radial spread of

activation from a focus, with endocardial activation

not extending through the entire atrial cycle. They

are usually manifest by atrial rates between 100

and 250 bpm (rarely at 300 bpm). The mechanism

has been attributed to abnormal or enhanced

automaticity, triggered activity (due to delayed after-

depolarization), or microre-entry. A progressive

increase in atrial rate with tachycardia onset

(“warm-up”) or progressive decrease before tachy-

cardia termination (“cool-down”) suggests an auto-

matic mechanism. Approximately 10% of patients

have multiple foci. Focal AT may be incessant,

leading to tachycardia-induced cardiomyopathy.

Treatment

Therapeutic options include use of drugs for rate

control (beta blockers, calcium-channel blockers,

or digoxin) or for suppression of the arrhythmic

focus. In addition, class Ia or Ic (flecainide and

propafenone) drugs may prove effective.

The available studies suggest use of IV adenosine,

beta blockers, or calcium-channel blockers either

for acute termination (unusual) or more frequently

to achieve rate control. Adenosine will terminate

focal AT in a significant number of patients. DC

Recommendations for Long-Term Therapy of Accessory Pathway-Mediated Arrhythmias

Arrhythmia Recommendation Class Evidence

WPW syndrome (pre-excitation and sympto-matic arrhythmias),well tolerated

WPW syndrome (with AFand rapid-conduction orpoorly tolerated AVRT)

AVRT, poorly tolerated (no pre-excitation)

Single or infrequent AVRT episode(s) (no pre-excitation)

Pre-excitation,asymptomatic

The order in which treatment recommendations appear in this table within each class of recommendation does notnecessarily reflect a preferred sequence of administration. Please refer to text for details. For pertinent drug dosinginformation, please refer to the ACC/AHA/ESC Guidelines for the Management of Patients With Atrial Fibrillation.

AF indicates atrial fibrillation; AVRT, atrioventricular reciprocating tachycardia; WPW, Wolff-Parkinson-White.

26 27

Specific Arrhythm

iasSpec

ific

Arr

hyth

mia

s

Catheter ablation I BFlecainide, propafenone IIa CSotalol, amiodarone, beta blockers IIa CVerapamil, diltiazem, digoxin III C

Catheter ablation I B

Catheter ablation I BFlecainide, propafenone IIa CSotalol, amiodarone IIa CBeta blockers IIb CVerapamil, diltiazem, digoxin III C

None I CVagal maneuvers I B“Pill-in-the-pocket”— verapamil, diltiazem, beta blockers I BCatheter ablation IIa BSotalol, amiodarone IIb BFlecainide, propafenone IIb CDigoxin III C

None I CCatheter ablation IIa B

Recommendations for Treatment of Focal Atrial Tachycardias*

Clinical Situation Recommendation Class Evidence

Acute treatment†

A. Conversion

Hemodynamicallyunstable patient

Hemodynamically stable patient

B. Rate regulation (in absence of digitalis therapy)

Prophylactic therapy

Recurrent symptomatic AT

Asymptomatic or symptomatic incessant ATs

Nonsustained and asymptomatic ATs

2928

cardioversion seldom terminates automatic ATs but may

be successful for ATs based on microre-entry or triggered

automaticity and should be attempted in patients with drug-

resistant arrhythmia.

Chronic control involves initial use of AV-nodal–blocking drugs

because they may prove effective and they have minimal side

effects. Other, more potent agents should be reserved for after

failure of an AV-nodal blocker. Focal AT is ablated by targeting

the site of origin of the AT. Catheter ablation has a success rate

of 80% to 90% for right atrial foci and 70% to 80% for left atrial

foci. The incidence of significant complications is low (1% to

2%). Ablation of AT from the atrial septum or Koch’s triangle

may produce AV block.

Multifocal Atrial Tachycardia

This tachycardia is characterized by finding three or more

different P-wave morphologies at different rates. The rhythm

is always irregular and frequently confused with AF. It is most

commonly associated with underlying pulmonary disease but

may result from metabolic or electrolyte derangements. Therapy

includes correction of underlying abnormalities but often

requires use of calcium-channel blockers, because there is no

role for DC cardioversion, antiarrhythmic drugs, or ablation.

Specific Arrhythm

iasSpec

ific

Arr

hyth

mia

s

The order in which treatment recommendations appear in this table within each class of recommendation does notnecessarily reflect a preferred sequence of administration. Please refer to text for details. For pertinent drug dosinginformation, please refer to the ACC/AHA/ESC Guidelines for the Management of Patients With Atrial Fibrillation.

*Excluded are patients with multifocal AT in whom beta blockers and sotalol are often contraindicated because of pulmonary disease.

† All listed drugs for acute treatment are taken intravenously.

‡ Flecainide, propafenone, and disopyramide should not be used unless they are combined with an AV- nodal–blocking agent.

AT indicates atrial tachycardia; DC, direct current.

DC Cardioversion I B

Adenosine IIa CBeta blockers IIa CVerapamil, diltiazem IIa CProcainamide IIa CFlecainide, propafenone IIa CAmiodarone, sotalol IIa C

Beta blockers I CVerapamil, diltiazem I CDigoxin IIb C

Catheter ablation I BBeta blockers,calcium-channel blockers I CDisopyramide‡ IIa CFlecainide, propafenone‡ IIa CSotalol, amiodarone IIa C

Catheter ablation I B

No therapy I CCatheter ablation III C

30 31

F. Macro–Re-entrant Atrial Tachycardia

Atrial flutter is defined as an organized rapid (250 to

350 bpm) macro–re-entrant atrial rhythm. The most

common forms relate to re-entrant rhythms that cir-

culate around the tricuspid annulus. Isthmus-depen-

dent flutter refers to circuits in which the arrhythmia

involves the cavotricuspid isthmus (CTI). They are

most frequently manifest as counterclockwise (neg-

ative flutter deflections in inferior leads) but can be

clockwise (positive deflections in the inferior leads).

Non–isthmus-dependent atrial flutter is less frequent

and is often caused by surgical scars that produce

a central obstacle for re-entry. For patients with

non–isthmus-dependent flutter, large areas of atrial

scar are found (with cardiac mapping) and are often

associated with multiple re-entrant circuits. Atrial

flutter may cause insidious symptoms, such as

exercise-induced fatigue, worsening heart failure,

or pulmonary disease. Patients often present with

a 2:1 AV conduction, which, if left untreated, may

promote cardiomyopathy.

Treatment

Acute therapy depends on the clinical status of the

patient and underlying cardiorespiratory problems. If

the arrhythmia is attended by heart failure, shock, or

myocardial ischemia, then prompt DC cardioversion

is in order. Rapid atrial (or esophageal pacing) and

low-energy DC cardioversion are very effective in

termination of atrial flutter. In most instances, how-

ever, patients with flutter are stable, and trials of

AV-nodal–blocking drugs for rate control are in

order. This is especially important if the subsequent

use of antiarrhythmic drugs is planned, because

slowing of the flutter rate by antiarrhythmic drugs

(especially class Ic drugs) may result in a paradoxical

increase in the ventricular rate. If the atrial flutter

persists longer than 48 hours, then either a 3- to 4-

week course of anticoagulant therapy or a negative

transesophageal echocardiogram (absence of clots) is

Specific Arrhythm

iasSpec

ific

Arr

hyth

mia

s

▼

DC cardioversion

Antiarrhythmic drugs Catheter ablation

Conversion■ DC cardioversion■ Atrial pacing■ Pharmacologicalconversion

▼

Rate control:AV-nodal blockers

▼ ▼

33

advisable before electrical or drug conversion is

attempted. These recommendations are identical to

those used for management of atrial fibrillation.

Neither AV-nodal drugs nor amiodarone is effective

for conversion of atrial flutter. Intravenous ibutilide

appears to be the most effective agent for acute drug

termination of flutter, with an efficacy between 38%

and 76%, and is more effective than intravenous

Class Ic agents.

Class III drugs, especially dofetilide, appear to be quite

effective chronic therapy for patients with flutter (73%

response rate). Chronic therapy is usually not required

after sinus rhythm is restored if atrial flutter occurs as

part of an acute disease process.

Catheter ablation of the CTI is a safe and effective

cure for patients with CTI-dependent flutter. For

those patients with non–isthmus-dependent flutter,

referral to a specialized center is in order because

multiple complex circuits are frequently found.

Success rates vary from 50% to 88% depending on

lesion complexity.

32

Specific Arrhythm

iasSpec

ific

Arr

hyth

mia

s

Figure 7

Management of atrial flutter depending on hemodynamic stability.

Attempts to electively revert atrial flutter to sinus rhythm should be preceded and followed by anticoagulant precautions, as per atrial fibrillation.AV, atrioventricular; CHF, congestive heart failure; DC, direct current; MI, myocardial infarction.

Atrial flutter

Unstable Stable▼ ▼

▼ ▼

CHF, shock, acute MI

If therapy for prevention of recurrences warranted

34 35

Recommendations for Acute Management of Atrial Flutter

Clinical Status/Proposed Therapy Recommendation* Class Evidence

Poorly tolerated

Conversion

Rate control

Stable flutter

Conversion

Rate control

Recommendations for Long-Term Management of Atrial Flutter

Clinical Status/Proposed Therapy Recommendation Class Evidence

First episode and well-tolerated atrial flutter

Recurrent and well-tolerated atrial flutter

Poorly tolerated atrial flutter

Atrial flutter appearingafter use of class Icagents or amiodarone for treatment of AF

Symptomatic non–CTI-dependent flutter afterfailed antiarrhythmic drug therapy

Specific Arrhythm

iasSpec

ific

Arr

hyth

mia

s

The order in which treatment recommendations appearin this table within each class of recommendation doesnot necessarily reflect a preferred sequence of adminis-tration. Please refer to text for details. For pertinent drugdosing information, please refer to the ACC/AHA/ESCGuidelines for the Management of Patients With Atrial Fibrillation.

Cardioversion should be considered only if the patient is anticoagulated (international normalized ratio equals 2 to 3), the arrhythmia is less than 48 hours in duration,or the transesophageal echocardiogram shows no atrialclots.

*All listed drugs are taken intravenously.

† Digitalis may be especially useful for rate control in patients with heart failure.

‡ Ibutilide should not be used in patients with reduced left ventricular function.

§ Flecainide, propafenone, and procainamide should not beused unless they are combined with an atrioventricular-nodal–blocking agent.

DC indicates direct current.

Cardioversion alone I B

Catheter ablation* IIa B

Catheter ablation* I B

Dofetilide IIa C

Amiodarone, sotalol, flecainide,†‡

quinidine,†‡ propafenone,†‡

procainamide,†‡ disopyramide†‡ IIb C

Catheter ablation* I B

Catheter ablation* I B

Stop current drug and use another IIa C

Catheter ablation* IIa B

The order in which treatment recommendations appear in this table within each class of recommendation does notnecessarily reflect a preferred sequence of administration. Please refer to text for details. For pertinent drug dosinginformation, please refer to the ACC/AHA/ESC Guidelines for the Management of Patients With Atrial Fibrillation.

* Catheter ablation of the AV junction and insertion of a pacemaker should be considered if catheter ablative cure isnot possible and the patient fails drug therapy.

† These drugs should not be taken by patients with significant structural cardiac disease. Use of anticoagulants isidentical to that described for patients with AF.

‡ Flecainide, propafenone, procainamide, quinidine, and disopyramide should not be used unless they are combinedwith an atrioventricular nodal–blocking agent.

AF indicates atrial fibrillation; CTI, cavotricuspid isthmus.

DC cardioversion I C

Beta blockers IIa CVerapamil, diltiazem IIa CDigitalis† IIb CAmiodarone IIb C

Atrial or transesophageal pacing I ADC cardioversion I CIbutilide ‡ IIa AFlecainide§ IIb APropafenone§ IIb ASotalol IIb CProcainamide§ IIb AAmiodarone IIb C

Diltiazem, verapamil I ABeta blockers I CDigitalis† IIb CAmiodarone IIb C

36 37

G. Special Circumstances

1. Pregnancy

SVA occurring during pregnancy may be a

particularly difficult problem. There is concern

about the hemodynamic effects on the mother and

fetus and the possible adverse drug effects on the

fetus. Certain principles should be emphasized.

1) Arrhythmias curable by ablation should be

seriously considered before planned pregnancy.

2) Most arrhythmias consist of isolated atrial or ven-

tricular premature beats and do not require therapy.

3) Acute therapy of arrhythmias should be directed

at use of nonpharmacological approaches (i.e.,

vagal maneuvers). Intravenous adenosine and DC

cardioversion have been shown to be safe. The

major concern with antiarrhythmic drug treatment

during pregnancy is the potential for adverse effects

on the fetus. The first 8 weeks after conception are

associated with the greatest teratogenic risk.

Adverse effects on fetal growth/development are

the major risks during the second and third

trimesters. Antiarrhythmic drug therapy should

only be used if symptoms are intolerable or if the

tachycardia causes hemodynamic compromise.

Recommendations for Treatment Strategies for SVT During Pregnancy (PC1)

Treatment Strategy Recommendation Class Evidence

Acute conversion of PSVT

Prophylactic therapy

Spec

ific

Arr

hyth

mia

s Specific Arrhythm

ias

The order in which treatment recommendations appear in this table within each class of recommendation does not necessarily reflect a preferred sequence of administration. Please refer to text for details. For pertinent drug dosing information, please refer to the ACC/AHA/ESC Guidelines for the Management of Patients With Atrial Fibrillation.

* Beta-blocking agents should not be taken in the first trimester, if possible.

† Consider atrioventricular nodal–blocking agents in conjunction with flecainide and propafenone for certain tachycardias (see Section V).

‡ Atenolol is categorized in class C (drug classification for use during pregnancy) by legal authorities in some European countries.

DC indicates direct current; PSVT, paroxysmal supraventricular tachycardia.

Vagal maneuver I CAdenosine I CDC cardioversion I CMetoprolol, propranolol IIa CVerapamil IIb C

Digoxin I CMetoprolol* I BPropranolol* IIa BSotalol,* flecainide† IIa CProcainamide IIb BQuinidine, propafenone,† verapamil IIb CCatheter ablation IIb CAtenolol‡ III BAmiodarone III C

38 39

2. Adults With Congenital Heart Disease

The treatment of SVT in adult patients with repaired

or unrepaired congenital heart disease is often com-

plicated and should be managed at experienced

centers. SVAs are an important cause of morbidity

and, in some patients, mortality. These patients

often have multiple atrial circuits or mechanisms

responsible for arrhythmias. Atrial arrhythmias can

indicate deteriorating hemodynamic function, which

in some cases warrants specific investigation and

operative treatment. Coexistent sinus node dysfunc-

tion is common, requiring pacemaker implantation

to allow management of SVTs. Cardiac malforma-

tions often increase the difficulty of pacemaker

implantation and catheter ablation procedures. In

addition, arrhythmia therapy by either drugs or

catheter ablation must be coordinated properly

within the context of surgical repair.

Specific Arrhythm

iasSpec

ific

Arr

hyth

mia

s

* Conversion and antiarrhythmic drug therapy for initial management as described for atrial flutter.

ASD indicates atrial septal defect; PSVT, paroxysmal supraventricular tachycardia.

Recommendations for Treatment of SVTs in Adults With Congenital Heart Disease

Condition Recommendation Class Evidence

Failed antiarrhythmic drugs and symptomatic:

■ Repaired ASD

■ Mustard or Senningrepair of transpositionof the great vessels

Unrepaired asympto-matic ASD that is not hemodynamically significant

Unrepaired hemody-namically significant ASD with atrial flutter*

PSVT and Ebstein’s anomaly with hemo-dynamic indications for surgical repair

Catheter ablation in an experienced center I C

Catheter ablation in an experienced center I C

Closure of the ASD for treatment of the arrhythmia III C

Closure of the ASD combined with ablation of the flutter isthmus I C

Surgical ablation of accessory pathways at the time of operative repair of the malformation at an experienced center I C

40